How Reliable Are Our Memories?

Recently I found a diary that I’d written when I was 17. Like so many people, my memories of that time feel extremely vivid and important. Psychological research backs this up, consistently finding that adolescent memories are unusually powerful and easily accessed. This is hardly surprising given that the cusp of adulthood is such a crucial period in finding our identity, forming new relationships and making life-changing plans. Rehearsing those memories helps us to feel grounded. But how reliable are those memories? Do they tell us the truth or do they just tell us what we want to remember?

This question lies at the crux of Ritesh Batra’s new film, The Sense of an Ending, in which Tony Webster receives a letter out of the blue, bequeathing him the diary of a close friend from many years ago. As the film unfolds, it becomes clear that Webster, brilliantly portrayed by Jim Broadbent, has created a narrative for himself that only partly reflects reality. He is forced to update not only his own, but other life stories, as he comes face to face with new pieces of evidence and some uncomfortable truths.

This film provides a lovely illustration of something that memory scientists have known for a long time – that some aspects of human memory are very malleable. When it comes to knowing where we live, or what colour a tomato is, we are pretty reliable. But when it comes to recollecting journeys we have taken or conversations we’ve had, our memories are far less accurate.

Apart from anything else, these memories for experience – our autobiographical memories – can only ever be constructed from our perceptions of what happened, which may well differ from someone else’s. We also make inferences, either at the time or later, which are heavily influenced by what we know and how we feel. Most importantly, we tend to let go of details that don’t sit comfortably with our sense of who we are or who we want to be. And by the same token, we rehearse and embellish those parts of the experience that confirm our identity and support our life goals.

So should we be worried that we are continually writing and re-writing our own history like this? On the contrary, psychologists have argued that this flexibility is an important part of being a happy human being. The capacity to actively shape our narrative enables us to have a coherent and stable sense of identity.

Nevertheless, we have to acknowledge that all experience influences us, regardless of whether we have conscious access to it or not. And, like Webster, we may occasionally be forced to confront things that we had selectively written out of our story. Similarly, we may come up against new evidence or testimony that prompts us to reframe memories that we have held for a long time. Sometimes this can be painful, other times it can be cathartic. For me, revisiting my 17 …